Buoyant fishing line

ABSTRACT

A buoyant fishing line comprising a foamed core surrounded by a filamentous line with or without being coated with a flexible surface layer.

[ Nov. 26, 1974 1 BUOYANT FISHING LINE 2,862,282 3,043,045 7/1962Martuch 12/1969 [75] Inventor: Leon L. Martuch, Midland, Mich.

3,486,266 Richardson et al.. 161/175 3,523,034 8/1970 H0wa1d........,...3,546,060

[73] Assignee: Scientific Anglers, Inc., Midland,

5/1967 Hoppe et a],

Mich.

[22] Filed: Jan. 27, 1972 Primary Examiner-George F. Lesmes AssistantExaminer-James J. Bell Attorney, Agent, or Firm-Laurence, Laurence &

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[21] Appl. No.: 221,148

coated with a flexible surface layer.

9 Claims, 3 Drawing Figures [56] References Cited UNITED STATES PATENTSBACKGROUND OF INVENTION This invention relates to an improved buoyantfishing line. This invention further relates to an improved buoyantfishing line having a foamed core. This invention still further relatesto a process for preparing the improved buoyant fishing line of thisinvention.

A good buoyant line for fly casting should have, besides buoyancy, atleast the following properties: (1) weight sufficient for casting; (2)little visibility for the fish; (3) flexibility; and (4) retain itsbuoyancy with I use.

Since the lure usually has little weight, the propelling force for acast is generated initially in the line and then transmitted to theleader and lure. The fishing line therefore should have sufficientweight for the force to develop and be transmitted.

The diameter of the line should be relatively small to reduce itsvisibility to the fish and avoid friction with the guides during thecast. A visible line will distract the fish away from the lure.

A good line should also be flexible and retain its flexibility. If theline is not sufficiently flexible it will not generate sufficientenergy, nor transmit the energy necessary for proper casting.

Retention of buoyancy is another feature required for a good line. Manylines, during use, develop cracks in the surface coating permittingwater to enter the line decreasing the buoyancy of the line and alsoweakening or breaking the bond between the line and the coating. Theline therefore becomes useless after a relatively short period of use.

Many attempts have been made to overcome these disadvantages, mostwithout success. The lines developed as a result of these attemptseither did not overcome all the disadvantages or developed newdisadvantages in the process.

Increased buoyancy of a line by the incorporation of microbeads orfoaming of the surface coating has been attempted. Both methods increasethe lines diameter decreasing its flexibility and increasing itsvisibility to the fish. The surface coating is also weakened by theincorporation of particles, thus permitting cracking to occur andseepage of water into the lines center.

The incorporation of buoyant material in a surface coating cannot beused however to prepare a buoyant fishing line which does not requirethe additional weight imparted by the surface coating.

It is thus an object of this invention to overcome the disadvantagesenumerated above.

Another object of this invention is an improved buoyant fishing line.

Still another object of this invention is an improved buoyant fishingline having a foamed core.

Still another object of this invention is an improved buoyant fishingline having a foamed core but no surface coating. 9

These and other objects of this invention will be apparent from thedescription of the drawings and the following discussion.

DESCRIPTION OF THE DRAWINGS FIG. I is a drawing showing a longitudinalsection of a coated fishing line.

FIG. 2 is a cross-sectional view of a fishing line, along the line 2-2of FIG. 1.

FIG. 3 is a drawing showing a view with parts broken away of a fishingline. I

In the preparation of commercial fishing lines a filamentous material,such as nylon, dacron, silk and the like, is braided, twisted or laidside by side to provide the bulk of the line and its tensile strength.In most lines the filamentous material is braided and machines for thebraiding of this material are commercially available. Regardless of theprocess used for preparing the fishing line, a core is usually formedwithin the filamentous material. It is this core which, according to thepresent invention, is filled with a foamed material and which impartsthe improved buoyancy to the line.

In FIGS. 1 and 2, the foamed core material 1 is shown surrounded, orencased, in the filamentous line mate rial 2.

In FIG. 3, the filamentous line material is shown in a braided formwhich is the preferred form for the line material. It is also preferredthat the line material be nylon.

The core material 1 may be a monofilament or filaments of foamedmaterial or filamentous material (such as thread) impregnated or coatedwith foamed material.

The surface coating 3 of the line is any of the conventional coatingknown to those skilled in this art. The coating may be applied directlyto the line or there may be an intermediate adhesive (primer) layer. Itis preferred to have the intermediate adhesive layer. This improves theadherence of the surface coating to the line material. The primer shouldbe relatively non-viscous liquid which is compatible with the plastisolused as the surface coating. Suitable primers are vinyl chloride vinylacetate copolymer in methyl isobutyl ketone or acrylonitrile-butadienecopolymer in methyl-ethyl or methyl-isobutyl ketone.

After the primer has been applied and the solvent evaporated, thesurface coating plastisol is applied to the line.

The polymeric component of the plastisol may be vinyl chloride or vinylchloride copolymers. The poly mer is mixed with one or more plasticizersand a stabilizer.

Suitable plasticizers for vinyl chloride polymers include di-octyladipate, di-Z-ethylhexyl phthalate, dicapryl phthalate, tricresylphosphate and trioctyl phosphate.

Suitable stabilizers include lead, zinc and cadmium soaps and epoxides.The stabilizer is included to combine pick up with any hydrogen chloridewhich may be liberated from the polyvinyl chloride. Liberated hydrogenchloride, if not absorbed, will deteriorate the surface coating.

The amount of plasticizer present in the plastisol varies dependent uponthe polymer content but is usually in the range of about 30 to parts byweight of plasticizer per parts by weight of polyvinyl chloride.

After the line has been coated with the plastisol it is cured by heattreatment at a temperature in the range of about 350 to 380F.

A typical surface coating plastisol formulation, in parts by weight, isas follows:

Polyvinyl chloride (Geon 12!) 100 Dioctyl adipate 53 Epoxidized tall oil(Flexol E P8) 10 Lead soap 3 A typical plastisol formulation for afishing line has a specific gravity in the range of about 1.2 to 1.3. Inorder to have a buoyant fishing line, the resulting specific gravitymust be reduced. As was discussed previously, the specific gravity has,in the past, been reduced by the addition of microspheres of air in theplastisol and thus in the surface coating. The disadvantages of thisprocedure have been enumerated.

It has now been found that an improved buoyancy and an improved line isobtained by the addition of a foamed material to the core of the line.It should be pointed out that the definition of core as used in thisspecification and appended claims refers to that area within the lineproper, such as the area within a braided nylon line. In the prior artthe term core refers to the braided nylon line itself.

In the process for the production of a fishing line, such as thebraiding of nylon filaments or fibers, a hollow area within the centerof the line is formed. It is this hollow area which is referred to asthe core in this application and which is substantially occupied by afoamed material. The diameter of this core varies with the means ofproducing the line. It is usually in the range of about 0.005 to 0.015inch.

In most commercial lines, this core remains empty and any air in thecore aids in the buoyancy of the line. However, when a crack develops inthe surface coating, any water which enters the line eventually reachesthe core and fills the core. This decreases the buoyancy of the linebecause (1) the air in the core is displaced by water, and (2) an addedweight, water, is supplied to the line. Because of the small diameter ofthe core, it is extremely difficult to dry out the water in the core.The line, therefore, rapidly becomes useless.

The presence of a foamed material, according to this invention, in thecore prevents any significant amount of water to enter the core. Inaddition, since the air is trapped within the foamed core material itcannot be displaced. Buoyancy of the line is thus maintained.

The foamed material, which substantially fills the core, can either be athread material impregnated or coated with foamed material, or befilaments of foamed material.

In either case, the material may be foamed prior to incorporation in theline or after incorporation in the line.

As was discussed previously, in the production of a fishing line, asurface coating, when used, is applied to the line in the form ofa-plastisol which is then cured. It is possible to take advantage ofthis curing step to also foam the core material. Many syntheticcompositions are available which will expand upon heating forming acellular structure. This material incorporated within the core willexpand during the curing (heating) step and substantially occupy thecore space.

The other process utilizes a foamed material and braids the line aroundthe foamed material. In this process, the diameter of the foamedmaterial may be slightly larger than the normal diameter range of theinner core of a fishing line. The line as it is being braided willcompress the foamed material thus ensuring that the core will besubstantially occupied by the foamed material.

Preparation of a thread, such as cotton or nylon, impregnated with afoamable material can be prepared utilizing conventionally knownprocesses, such as described in US. Pat. No. 3,479,811.

One of the processes comprises the feeding of the thread to a tankcontaining a foamable coating mixture. As the thread passes through thecoating mixture, the coating adheres to the thread. The amount ofcoating which will adhere to the thread can be regulated by the speedwith which the thread is passed through the coating mixture. Anothermeans by which the amount of coating adhering to the thread is regulatedis by passing the thread, after it leaves the tank, through anadjustable orifice. The excess coating is removed during the passagethrough the orifice.

This procedure provides mainly a surface coating on the thread. However,depending upon the viscosity of the mixture, some impregnation occurs.The more fluid the liquid, the greater the degree of impregnation.

Coating mixtures of foamable material are commercially available oreasily prepared. Polystyrene beads are available in bead diameters of0.8 mm and less. The beads containing a low boiling aliphatic solventand foaming occurs at about 200F.

Vinyl and polyethylene beads and pellets are also commerciallyavailable. The foaming agent varies and may be a chemical or a lowboiling solvent.

Other beads and pellets and other diameters are also available.

These are just a small number of the commercial available products whichmay be utilized.

The coated and/or impregnated thread is then dried to remove thesolvent. If the material is to be foamed prior to incorporating into theline, the removal of solvent can be conducted at a higher temperature orunder conditions which would also foam the coating mixture. If foamingis to be delayed then the solvent is removed under milder temperature orconditions to prevent foaming.

In either case, the resultant thread is then encompassed within afishing line. This may be accomplished by passing the thread up throughthe center of a braiding machine and have the line braided around thecoated thread. Machines capable of accomplishing this process arecommercially available or can be easily adapted.

The line with its foamed or foamable core is then coated with a primerand finally the surface coating.

As was discussed previously, most line coatings are cured at elevatedtemperatures. This curing step will also foam the core material ifnecessary. It should be remembered that the temperature in the core willbe less than at the surface of the line. It may thus be necessary tocure the surface coating at a temperature in the upper portion of therange in order to supply suffrciently high temperatures to cure the corematerial. It is not necessary, and in many instances it will not berequired, that the core material and surface material require the sametemperature for foaming and curing, respectively.

Foaming of the core material and curing of the surface coating at thesame time requires a better control over operating conditions thanrequired when only curing of the surface coating occurs.

In addition, there always exists the possibility that during the foamingof the core material some gas might escape and rupture or blister thesurface coatings. For these reasons it is preferrable that the corematerial be foamed prior to being encompassed by the line material.

The procedure for the preparation of a buoyant line utilizing as a corematerial filaments or a filament of a foamed or formable material isbasically similar to that previously discussed for the coated thread.The main difference between the two processes resides in the preparationof the core material. Foamed or foamable filaments are commerciallyavailable or easily prepared by known methods and do not have to becoated as discussed previously for the thread. Their incorporation intothe fishing line and subsequent treatment, if necessary, is similar tothe coated thread operation already discussed.

In another embodiment of this invention, the buoyant fishing line hasthe same buoyant filamentous center andline as previously discussed butdoes not have a flexible outer surface coating. This type of line isdesirable where the buoyancy feature is desired but the added weight dueto the surface coating is not needed or desired.

The process for preparing this type of line is identical with theprevious discussion. Since there is no surface coating, foaming of thecore can be delayed until after the line has been formed around thefoamable core material.

While the illustrative embodiments of the invention have been describedhereinbefore with particularity, it will be understood that variousother modifications will be apparent to and can readily be made by thoseskilled in the art without departing from the scope and spirit of theinvention. Accordingly, it is not intended that the scope of the claimsappended hereto be limited to the examples and description set forthherein but rather the claims be construed as encompassing all thefeatures of patentable novelty which reside in the present inventionincluding all features which would be treated as equivalents thereof bythose skilled in the art to which the invention pertains.

I claim:

1. A buoyant fishing line dimensioned to be suitable for fly casting andincluding a flexible castable filamentous line having a braidedconfiguration with an open center, a foamed threadJike coresubstantially completely occupying said open center and extending thelength thereof to impart buoyancy to said fishing line, and a flexiblesurface coating on said filamentous line.

2. A buoyant fishing line according to claim 1, fur ther comprising aprimer coating interposed between said filamentous line and saidflexible surface coating.

3. A buoyant fishing line according to claim ll, wherein said core is athread incorporating foamed material.

4. A buoyant fishing line according to claim 1, wherein said core iscomprised of filamentous foamed material.

5. A buoyant fishing line according to claim 1, wherein said filamentousline is a braided nylon line and wherein said flexible surface coatingis comprised of polyvinyl chloride, and further comprising a primer onthe surface of said nylon line beneath said flexible surface coating.

6. A buoyant fishing line according to claim 4 wherein said foamed coreis a monofilament foamed material.

7. A buoyant fishing line according to claim 1 wherein said filamentousline is selected from the group consisting of nylon, dacron and silk.

8. A buoyant fishing line according to claim 7 wherein said filament isnylon.

9. A buoyant fishing line according to claim 8 wherein said foamed coreis a thread incorporating

1. A buoyant fishing line dimensioned to be suitable for fly casting andincluding a flexible castable filamentous line having a braidedconfiguration with an open centeR, a foamed thread-like coresubstantially completely occupying said open center and extending thelength thereof to impart buoyancy to said fishing line, and a flexiblesurface coating on said filamentous line.
 2. A buoyant fishing lineaccording to claim 1, further comprising a primer coating interposedbetween said filamentous line and said flexible surface coating.
 3. Abuoyant fishing line according to claim 1, wherein said core is a threadincorporating foamed material.
 4. A buoyant fishing line according toclaim 1, wherein said core is comprised of filamentous foamed material.5. A buoyant fishing line according to claim 1, wherein said filamentousline is a braided nylon line and wherein said flexible surface coatingis comprised of polyvinyl chloride, and further comprising a primer onthe surface of said nylon line beneath said flexible surface coating. 6.A buoyant fishing line according to claim 4 wherein said foamed core isa monofilament foamed material.
 7. A buoyant fishing line according toclaim 1 wherein said filamentous line is selected from the groupconsisting of nylon, dacron and silk.
 8. A buoyant fishing lineaccording to claim 7 wherein said filament is nylon.
 9. A buoyantfishing line according to claim 8 wherein said foamed core is a threadincorporating foamed material.